1. Field of the Invention
The present invention relates to an oxygen sensor bung of motor vehicle exhaust pipe to increase process area of exhaust gas to reduce impurities in the exhaust gas and allow timely replacement of catalytic converter to achieve accurate detection of oxygen content.
2. Description of the Prior Art
Conventional techniques to detect exhaust gas of motor vehicles generally are accomplished through an oxygen sensor (O2 sensor in short hereinafter) to monitor whether catalyst functions properly. However, the exhaust gas often contains impurities that could clog the O2 sensor and affect detection accuracy, such as exhaust gas flow speed, duty temperature and contents cannot be accurately judged that could result in not proper signaling of engine alarm lights and even impact engine fuel injection and ignition system.
To remedy the aforesaid problems many techniques have been proposed in prior art. For instance R.O.C. patent M375123 discloses a bung with the interior coated with a catalyst conversion agent to reduce impurities in the exhaust gas. In practice it still has drawbacks, notably:
1. The thin layer of catalyst conversion agent coated in the interior does not have sufficient process area and is easily peeled off and becomes dysfunctional.
2. Once the catalyst conversion agent is dysfunctional it cannot be recoated again, and the entire set has to be replaced. Hence the cost of repairs and maintenance is higher.
3. The coated catalyst conversion agent cannot fully process the impurities in the exhaust gas and could result in inaccurate detection of the O2 sensor and affect maneuverability of vehicles during driving.